Method for fabricating heat-dissipating base structure

ABSTRACT

A method for fabricating a heat-dissipating base structure is disclosed. The method includes (1) providing a plurality of heat-dissipating fins arranged in parallel, each having at least a first through hole and a second through hole corresponding to the first through hole formed thereon at corresponding positions; (2) providing at least a U-shaped heat-dissipating tube having two tube foot portions and a bending portion, wherein the diameter of the two tube foot portions is smaller than that of the first and second through holes and the two tube foot portions are inserted into the first and second through holes respectively; (3) performing a dispensing process by penetrating a dispensing tip into the spacing between the U-shaped heat-dissipating tube and the first and second through holes of the heat-dissipating fins; (4) providing a base having a surface for dispensing and mounting the parallel-aligned heat-dissipating fins on the dispensed surface of the base; (5) using at least a clamp tool to tighten the base, the heat-dissipating fins and the U-shaped heat-dissipating tube to be placed in an oven for heating and the subsequent soldering process; and (6) removing the heat-dissipating base from the oven after the heating process and removing the clamp tool after the heat-dissipating base cools off and is fixedly assembled.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to a method for fabricating aheat-dissipating base structure, and more particularly to a method forfabricating a heat-dissipating base structure having a U-shapedheat-dissipating tube.

2. Description of Related Art

In a conventional heat-dissipating base having a heat-dissipating tube,in order to solder the heat-dissipating tube to heat-dissipating fins, adispensing process comprising the following steps has to be performed:first, a groove or a hole is formed on upper side of heat-dissipatingtube holes of the heat-dissipating fins, wherein the heat-dissipatingtube is inserted into the heat-dissipating fins through theheat-dissipating tube holes; then, a dispensing tip is inserted into thegroove or the hole so as to dispense solder paste between theheat-dissipating tube and the heat-dissipating fins, the solder paste ata melting state further flows through the spacing between theheat-dissipating tube and the heat-dissipating fins by gravitationalforce and capillary force, thereby filling space between theheat-dissipating tube and the heat-dissipating fins. However, thenatural drain down of the solder paste cannot ensure theheat-dissipating tube and the heat-dissipating fins are completelysoldered together. If the heat-dissipating tube and the heat-dissipatingfins are not completely soldered together, the heat transfer effect fromthe heat-dissipating tube to the heat-dissipating fins will be adverselyaffected, which further adversely affects the heat-dissipatingefficiency of the heat-dissipating base.

Referring to FIGS. 1A and 1B, a conventional heat-dissipating basehaving a heat-dissipating tube comprises a base 10; a plurality ofheat-dissipating fins 11 arranged in parallel and disposed on the base10, wherein each of the fins 11 has a plurality of heat-dissipating tubeholes 110; and a U-shaped heat-dissipating tube 20, two tube footportions of which are inserted into the heat-dissipating tube holes 110of the heat-dissipating fins 11. On upper side of the heat-dissipatingtube holes 110 there are disposed openings 111 as shown in FIG. 1A orgrooves 112 as shown in FIG. 1B such that a dispensing tip (not shown)can be inserted into inside of the heat-dissipating fins 11 through theopenings 111 or the grooves 112 for dispensing such that solder pastecan be attached to the U-shaped heat-dissipating tube 20.

As shown in FIG. 2A, after a dispensing process is performed to thestructure of FIG. 1B, the whole heat-dissipating base structure is putinto an oven such that the solder paste 21 can be melted. The meltedsolder paste 21 further flows through and fills spacing between theheat-dissipating tube 20 and the heat-dissipating tube holes 110 of theheat-dissipating fins 11 by gravitational force and capillary force,thereby soldering together the U-shaped heat-dissipating tube 20 and theheat-dissipating fins 11.

However, the natural drain down of the solder paste 21 cannot ensure theheat-dissipating tube and the heat-dissipating fins are completelysoldered together. As shown in FIG. 2B, spacing between the lowerportion of the U-shaped heat-dissipating tube 20 and theheat-dissipating tube holes 110 of the heat-dissipating fins 11 is notfilled with the solder paste 21, which can adversely affect the heattransfer effect from the heat-dissipating tube 20 to theheat-dissipating fins 11 and the heat-dissipating effect of theheat-dissipating base.

Further, since the diameter of the heat-dissipating tube holes 110corresponds to the diameter of the U-shaped heat-dissipating tube 20,once the U-shaped heat-dissipating tube 20 is inserted into theheat-dissipating tube holes 110, the U-shaped heat-dissipating tube 20cannot make any displacement. Therefore, it is not possible to perform adispensing process to the lower tube foot portion of the U-shapedheat-dissipating tube 20. Correspondingly, an opening or a groovesimilar to the above-mentioned opening or groove also needs to be formedfor allowing a dispensing tip to enter into inside of theheat-dissipating fins such that the lower tube foot portion can besoldered to the heat-dissipating fins. However, in the prior art, nosuch opening or groove is formed taking into account of such factors asheat-dissipating area. Instead, the lower tube foot portion of theU-shaped heat-dissipating tube 20 is kept separated from theheat-dissipating fins 11, which thus leads to a poor heat conductiontherebetween and accordingly reduces the heat-dissipating effect of theheat-dissipating base.

Therefore, how to overcome the above drawback has become urgent.

SUMMARY OF THE INVENTION

According to the above drawbacks, an objective of the present inventionis to provide a method for fabricating a heat-dissipating base structurehaving heat-dissipating fins having elliptic through holes.

Another objective of the present invention is to provide a method forfabricating a heat-dissipating base structure, through which theheat-dissipating tube can obtain a good soldering effect.

A further objective of the present invention is to provide a method forfabricating a heat-dissipating structure having good heat-dissipatingefficiency.

In order to attain the above and other objectives, the present inventiondiscloses a method for fabricating a heat-dissipating structure, whereina heat-dissipating tube can be moved in the elliptic through hole andsecured fast to one side of the through hole.

The method for fabricating the heat-dissipating base structure comprisesthe steps of:

-   -   (1) providing a plurality of heat-dissipating fins arranged in        parallel, each having at least a first through hole and a second        through hole corresponding to the first through hole formed        thereon at corresponding positions;    -   (2) providing at least a U-shaped heat-dissipating tube having        two tube foot portions and a bending portion, wherein the        diameters of the two tube foot portions are smaller than the        diameters of the first and second through holes and the two tube        foot portions are inserted into the first and second through        holes respectively;    -   (3) performing a dispensing process by penetrating a dispensing        tip into the spacing between the U-shaped heat-dissipating tube        and the first and second through holes of the heat-dissipating        fins;    -   (4) providing a base having a surface for dispensing and        mounting the parallel-aligned heat-dissipating fins on the        dispensed surface of the base;    -   (5) using at least a clamp tool to tighten the base, the        heat-dissipating fins and the U-shaped heat-dissipating tube to        be placed in an oven for heating and the subsequent soldering        process; and    -   (6) removing the heat-dissipating base from the oven after the        heating process and removing the clamp tool after the        heat-dissipating base cools off and is fixedly assembled.

Preferably, the first and second through holes are elliptic. The firstand second through holes can be arranged in a vertical line or in ahorizontal line. The U-shaped heat-dissipating tube is fixed to one sideof the first and second through holes by a conductive material through asoldering method. The conductive material is one of gold, silver, solderpaste, and a mixture thereof. The clamp tool of step (5) comprises abase clamp and a heat-dissipating tube clamp, wherein theheat-dissipating tube clamp is a metal bar to be inserted into thespacing between the U-shaped heat-dissipating tube and the first andsecond through holes of the heat-dissipating fins so as to make the tubefoot portions of the U-shaped heat-dissipating tube closely attached toone side of the first and second through holes of the heat-dissipatingfins.

Compared with the prior art that solders the heat-dissipating tube andthe heat-dissipating fins together by forming little through holes forinserting of a dispensing tip so as to dispense the solder material andmake the soldering material fill the spacing between theheat-dissipating tube and the heat-dissipating fins through thegravitational force of the solder material and capillary force formed inthe spacing between the heat-dissipating tube and the heat-dissipatingfins, the present invention can make the heat-dissipating tube closelyattached and soldered to one side of the through holes by an externalforce so as to obtain a good heat conducting effect between theheat-dissipating tube and the heat-dissipating fins, thereby improvingthe heat-dissipating efficiency of the whole heat-dissipating basestructure.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1A is a diagram of a conventional heat-dissipating base structurehaving holes formed for insertion of a dispensing tip;

FIG. 1B is a diagram of a conventional heat-dissipating base structurehaving grooves formed for insertion of a dispensing tip;

FIG. 2A is a partially expanded diagram showing a state after solderpaste is dispensed to the structure of FIG. 1B;

FIG. 2B is a partially expanded diagram showing a soldering statebetween the heat-dissipating tube and the heat-dissipating fins of theheat-dissipating base structure of FIG. 2A;

FIG. 3 is a diagram showing a method for fabricating a heat-dissipatingbase structure according to a first embodiment of the present invention;

FIG. 4A is a diagram showing step (1) of the method for fabricating aheat-dissipating base structure according to a first embodiment of thepresent invention;

FIG. 4B is a diagram showing step (2) of the method for fabricating aheat-dissipating base structure according to a first embodiment of thepresent invention;

FIG. 4C is a diagram showing step (3) of the method for fabricating aheat-dissipating base structure according to a first embodiment of thepresent invention;

FIG. 4D is a diagram showing step (4) of the method for fabricating aheat-dissipating base structure according to a first embodiment of thepresent invention;

FIG. 4E is a diagram showing step (5) of the method for fabricating aheat-dissipating base structure according to a first embodiment of thepresent invention;

FIG. 4F is a diagram showing step (6) of the method for fabricating aheat-dissipating base structure according to a first embodiment of thepresent invention;

FIG. 5 is a diagram showing a method for fabricating a heat-dissipatingbase structure according to a second embodiment of the presentinvention;

FIG. 6A is a diagram showing step (1) of the method for fabricating aheat-dissipating base structure according to a second embodiment of thepresent invention;

FIG. 6B is a diagram showing step (2) of the method for fabricating aheat-dissipating base structure according to a second embodiment of thepresent invention;

FIG. 6C is a diagram showing step (3) of the method for fabricating aheat-dissipating base structure according to a second embodiment of thepresent invention;

FIG. 6D is a diagram showing step (4) of the method for fabricating aheat-dissipating base structure according to a second embodiment of thepresent invention;

FIG. 6E is a diagram showing step (5) of the method for fabricating aheat-dissipating base structure according to a second embodiment of thepresent invention;

FIG. 6F is a diagram showing step (6) of the method for fabricating aheat-dissipating base structure according to a second embodiment of thepresent invention;

FIG. 7 is a diagram showing a method for fabricating a heat-dissipatingbase structure according to a third embodiment of the present invention;

FIG. 8A is a diagram showing step (1) of the method for fabricating aheat-dissipating base structure according to a third embodiment of thepresent invention;

FIG. 8B is a diagram showing step (2) of the method for fabricating aheat-dissipating base structure according to a third embodiment of thepresent invention;

FIG. 8C is a diagram showing step (3) of the method for fabricating aheat-dissipating base structure according to a third embodiment of thepresent invention;

FIG. 8D is a diagram showing step (4) of the method for fabricating aheat-dissipating base structure according to a third embodiment of thepresent invention;

FIG. 8E is a diagram showing step (5) of the method for fabricating aheat-dissipating base structure according to a third embodiment of thepresent invention; and

FIG. 8F is a diagram showing step (6) of the method for fabricating aheat-dissipating base structure according to a third embodiment of thepresent invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The following illustrative embodiments are provided to illustrate thedisclosure of the present invention, these and other advantages andeffects can be apparent to those skilled in the art after reading thedisclosure of this specification. The present invention can also beperformed or applied by other different embodiments. The details of thespecification may be on the basis of different points and applications,and numerous modifications and variations can be made without departingfrom the spirit of the present invention.

FIG. 3 and FIGS. 4A to 4F are diagrams showing a method for fabricatinga heat-dissipating base structure according to a first embodiment of thepresent invention. The method comprises the following steps.

At step S301, a plurality of heat-dissipating fins 40 are provided, eachhaving at least an elliptic first through hole 41 and an elliptic secondthrough hole 42 corresponding to the first through hole 41 and alignedin a vertical line. The first through hole 41 is formed on an upper sideof the heat-dissipating fin 40 and the second through hole 42 is formedon a lower side of the heat-dissipating fin 40. The heat-dissipatingfins 40 are parallel to each other, as shown in FIG. 4A. Then, theprocess goes to step S302.

At step S302, two U-shaped heat-dissipating tubes 50 are provided, eachhaving two tube foot portions 51 and a bending portion 52. The diameterof the two tube foot portions 51 is smaller than diameter of the firstthrough hole 41 at short edges and the two tube foot portions 51 areinserted into the first and second through holes 41, 42 respectively. Inthe present step, the U-shaped heat-dissipating tubes 50 are disposed atlower sides of the first and second through holes 41, 42, as shown inFIG. 4B. Then, the process goes to step S303.

At step S303, a dispensing tip (not shown) is penetrated into thespacing between the U-shaped heat-dissipating tubes 50 and the first andsecond through holes 41, 42 for dispensing, and solder paste 60 iscoated to the two tube foot portions 51 of each U-shapedheat-dissipating tube 50. In the present embodiment, the solder paste 60is coated on upper sides of the two tube foot portions 51 of theU-shaped heat-dissipating tubes 50, as shown in FIG. 4C. Then, theprocess goes to step S304.

At step S304, a base 30 is provided which has a surface for dispensing,and the parallel-aligned heat-dissipating fins 40 are mounted on thedispensed surface of the base 30. The U-shaped heat-dissipating tubes 50are pressed toward the upper sides of the first and second through holes41, 42, as shown in FIG. 4D. Then, the process goes to step S305.

At step S305, a clamp tool (not shown) is used to tighten the base 30and the heat-dissipating fins to be placed in an oven (not shown) forheating and subsequent soldering, as shown in FIG. 4E. Then, the processgoes to step S306.

At step S306, the heat-dissipating base is removed from the oven afterthe heating process, and after the heat-dissipating base cools off andis fixedly assembled the clamp tool is removed. As shown in FIG. 4F, acompleted heat-dissipating base is shown.

In the first embodiment of the present invention, as the first andsecond through holes 41, 42 are vertically aligned, while the base 30and the heat-dissipating fins 40 are assembled together, the U-shapedheat-dissipating tubes 50 can be tightened by the clamp tool and pressedtoward the upper sides of the first and second through holes 41, 42.Thus, the U-shaped heat-dissipating tubes 50 are closely attached andsoldered to the upper sides of the first and second through holes 41,42. If the bending portions 52 of the U-shaped heat-dissipating tubes 50lack sufficient strength for making the tube foot portions 51 closelyattached to the upper sides of the first through holes 41, an additionalclamp tool can be used for making the tube foot portions 51 closelyattached to the upper side of the first through holes 41, which will bedescribed later.

FIG. 5 and FIGS. 6A to 6F show a method for fabricating a heatdissipating base structure according to a second embodiment of thepresent invention, which comprises the following steps.

At step S501, a plurality of heat-dissipating fins 40 is provided, eachhas an elliptic first through hole 41 and an elliptic second throughhole 42 corresponding to the first through hole 41, and the first andsecond through holes 41, 42 are aligned in a horizontal line. The firstand second through holes 41, 42 are located at central positions of theheat-dissipating fins 40. The heat-dissipating fins 40 are parallel toeach other, as shown in FIG. 6A. Then, the process goes to step S502.

At step S502, a U-shaped heat-dissipating tube 50 is provided, which hastwo tube foot portions 51 and a bending portion 52. The diameter of thetwo tube foot portions 51 is smaller than diameter of the first andsecond through holes 41, 42 at short edges and the two tube footportions 51 are inserted into the first and second through holes 41, 42respectively. In the present step, the U-shaped heat-dissipating tube 50is disposed at lower sides of the first and second through holes 41, 42,as shown in FIG. 6B. Then, the process goes to step S503.

At step S503, a dispensing tip (not shown) is penetrated into thespacing between the U-shaped heat-dissipating tube 50 and the first andsecond through holes 41, 42 for dispensing, and solder paste 60 iscoated to the two tube foot portions 51 of the U-shaped heat-dissipatingtube 50. In the present embodiment, the solder paste 60 is coated onupper sides of the two tube foot portions 51 of the U-shapedheat-dissipating tube 50, as shown in FIG. 6C. Then, the process goes tostep S504.

At step S504, a base 30 is provided which has a surface for dispensing,and the parallel-aligned heat-dissipating fins 40 are stack mounted onthe dispensed surface of the base 30 through the bending portion 52 ofthe heat-dissipating tube 50, and a heat-dissipating tube clamp tool,which is a metal bar 70 in the present embodiment, is inserted into thespacing between the lower sides of the tube foot portions 51 of theU-shaped heat-dissipating tube 50 and the first and second through holes41, 42 such that the two tube foot portions 51 can be pressed upward andclosely attached to the first and second through holes 41, 42, as shownin FIG. 6D. Then, the process goes to step S505.

At step S505, a clamp tool (not shown) is used to tighten the base 30and the heat-dissipating fins 40 to be placed in an oven (not shown) forheating and subsequent soldering, as shown in FIG. 6E. Then, the processgoes to step S506.

At step S506, the heat-dissipating base is removed from the oven afterthe heating process, and after the heat-dissipating base cools off andis fixedly assembled the metal bar 70 is removed. As shown in FIG. 6F, acompleted heat-dissipating base is shown.

In the second embodiment of the present invention, as the first andsecond through holes 41, 42 are horizontal aligned, while the base 30and the heat-dissipating fins 40 are assembled together, the U-shapedheat-dissipating tube 50 cannot be tightened at the same time andtherefore, a metal bar 70 is inserted into the spacing between the lowersides of the two foot tube portions 51 of the U-shape heat-dissipatingtube 50 and the first and second through holes 41, 42 so as to press theU-shaped heat-dissipating tube 50 toward the upper sides of the firstand second through holes 41, 42. Thus, the U-shaped heat-dissipatingtube 50 is closely attached and soldered to the upper sides of the firstand second through holes 41, 42.

FIG. 7 and FIGS. 8A to 8F show a method for fabricating a heatdissipating base structure according to a third embodiment of thepresent invention, which comprises the following steps.

At step S701, a plurality of heat-dissipating fins 40 is provided, eachhas an elliptic first through hole 41 and an elliptic second throughhole 42 corresponding to the first through hole 41, the first and secondthrough holes 41, 42 are horizontally arranged, and the major axes ofthe first and second through holes 41, 42 are in a horizontal line. Thefirst through hole 41 and the second through hole 42 are located atcentral positions of the heat-dissipating fins 40. The heat-dissipatingfins 40 are parallel to each other, as shown in FIG. 8A. Then, theprocess goes to step S702.

At step S702, a U-shaped heat-dissipating tube 50 is provided, which hastwo tube foot portions 51 and a bending portion 52. The diameter of thetwo tube foot portions 51 is smaller than diameter of the first andsecond through holes 41, 42 at short edges and the two tube footportions 51 are inserted into the first and second through holes 41, 42respectively. In the present step, the U-shaped heat-dissipating tube 50is disposed at left sides of the first and second through holes 41, 42,as shown in FIG. 8B. Then, the process goes to step S703.

At step S703, a dispensing tip (not shown) is penetrated into thespacing between the U-shaped heat-dissipating tube 50 and the first andsecond through holes 41, 42 for dispensing, and solder paste 60 iscoated to the two tube foot portions 51 of the U-shaped heat-dissipatingtube 50. In the present embodiment, the solder paste 60 is coated toright sides of the two tube foot portions 51 of the U-shapedheat-dissipating tube 50, as shown in FIG. 8C. Then, the process goes tostep S704.

At step S704, a base 30 is provided which has a surface for dispensing,and the parallel-aligned heat-dissipating fins 40 are stack mounted onthe dispensed surface of the base 30 through the bending portion 52 ofthe heat-dissipating tube 50, and a heat-dissipating tube clamp tool,which is a metal bar 70 in the present embodiment, is inserted into thespacing between the left sides of the tube foot portions 51 of theU-shaped heat-dissipating tube 50 and the first and second through holes41, 42 such that the two tube foot portions 51 can be pressed towardsand closely attached to the right sides of the first and second throughholes 41, 42, as shown in FIG. 8D. Then, the process goes to step S705.

At step S705, a clamp tool (not shown) is used to tighten the base 30and the heat-dissipating fins 40 to be placed in an oven (not shown) forheating and soldering, as shown in FIG. 8E. Then, the process goes tostep S706.

At step S706, the heat-dissipating base is removed from the oven afterthe heating process, and after the heat-dissipating base cools off andis fixedly assembled the heat dissipating base clamp tool and the metalbar 70 are removed. As shown in FIG. 8F, a completed heat-dissipatingbase is shown.

In the third embodiment of the present invention, as the first andsecond through holes 41, 42 are horizontal aligned and the major axes ofthe first and second through holes 41, 42 are in a horizontal line,while the base 30 and the heat-dissipating fins 40 are assembledtogether, the U-shaped heat-dissipating tube 50 cannot be tightened atthe same time and therefore, a metal bar 70 is inserted into the spacingbetween the left sides (or right sides) of the two foot tube portions 51of the U-shape heat-dissipating tube 50 and the first and second throughholes 41, 42 so as to press the U-shaped heat-dissipating tube 50 towardthe right sides of the first and second through holes 41, 42. Thus, theU-shaped heat-dissipating tube 50 is closely attached and soldered tothe right sides of the first and second through holes 41, 42.

Compared with the conventional method for fabricating theheat-dissipating base structure, the connecting manner between theheat-dissipating fins and the heat-dissipating tubes of the presentinvention has a better soldering effect, thereby providing aheat-dissipating base structure having firm soldering connection,requiring less fabrication time and capable of providing enhancedheat-dissipating efficiency.

The above-described descriptions of the detailed embodiments are only toillustrate the preferred implementation according to the presentinvention, and it is not to limit the scope of the present invention.Accordingly, all modifications and variations completed by those withordinary skill in the art should fall within the scope of presentinvention defined by the appended claims.

1. A method for fabricating a heat-dissipating base structure,comprising the steps of: (1) providing a plurality of heat-dissipatingfins arranged in parallel, each having at least a first through hole anda second through hole corresponding to the first through hole formedthereon at corresponding positions; (2) providing at least a U-shapedheat-dissipating tube having two tube foot portions and a bendingportion, wherein the diameter of the two tube foot portions is smallerthan that of the first and second through holes and the two tube footportions are inserted into the first and second through holesrespectively; (3) performing a dispensing process by penetrating adispensing tip into the spacing between the U-shaped heat-dissipatingtube and the first and second through holes of the heat-dissipatingfins; (4) providing a base having a surface for dispensing and mountingthe parallel-aligned heat-dissipating fins on the dispensed surface ofthe base; (5) performing a heating process by using at least a clamptool to tighten the base, the heat-dissipating fins and the U-shapedheat-dissipating tube to be placed in an oven for heating and asubsequent soldering process; and (6) removing the heat-dissipating basefrom the oven after the heating process and removing the clamp toolafter the heat-dissipating base is cooled off and is fixedly assembled.2. The method of claim 1, wherein the first through hole is elliptic. 3.The method of claim 1, wherein the second through hole is elliptic. 4.The method of claim 1, wherein the first through hole and thecorresponding second through hole are arranged in a vertical line. 5.The method of claim 1, wherein the first through hole and thecorresponding second through hole are arranged in a horizontal line. 6.The method of claim 1, wherein the U-shaped heat-dissipating tube isfixed to one side of the first and second through holes by a conductivematerial through a soldering method.
 7. The method of claim 6, whereinthe conductive material is one of gold, silver, solder paste, and amixture thereof.
 8. The method of claim 1, wherein the clamp tool of thestep (5) comprises a heat-dissipating tube clamp tool.
 9. The method ofclaim 8, wherein the heat-dissipating tube clamp tool is a metal bar,which is inserted into the spacing between the U-shaped heat-dissipatingtube and the first and second through holes of the heat-dissipating finsso as to make the tube foot portions of the U-shaped heat-dissipatingtube closely attached to one side of the first and second through holesof the heat-dissipating fins.